Lung border sweep upon phrenic stimulation: dynamic fall in pleural liquid pressure

Pleural pressure was measured by a capsule in 9th or 10th intercostal space (ics) of dogs during tetanic stimulation of phrenic nerves (PS). When lung border passed under capsule (bor.I) a marked negative spike occurred, reflecting pleural liquid pressure (Pliq). In 9th ics spike was briefer than during spontaneous breathing (SB), speed of lung border being 4.6 times greater. During PS spike was greater and longer in 10th than in 9th ics, lung volume at bor.I being 228 ml greater. Lung volume at bor.I was smaller during PS than passive inflation because of chest wall deformation. Dynamic fall in Pliq at bor.I has been estimated about 4 cm H2O during SB, and at least 12 and 16 cm H2O (in 9th and 10th ics, respectively) during PS. Dynamic fall in Pliq seems essentially a viscous loss: it increased with thinning of pleural liquid (increase in lung volume), and with speed and displacement of lung border. Results suggest that at ordinary lung volume viscous loss of pleural liquid in this region is about 2 cm H2O per cm displacement at a speed of 1 cm/sec.     

Electrolyte transport across the pleura of rabbits.

The amounts of Na+ and Cl- in the right pleural space of anesthetized rabbits were determined 10 and 60 min after a 2 ml hydrothorax with the following solutions: Ringer, Ringer with an inhibitor of the Na(+)-Cl- coupled transport or of the Na+/K+ pump, Ringer with gluconate instead of Cl- or with methylglucamine instead of Na+. During the 10-60 min period: (a) with Ringer Na+ and Cl- decreased (P less than 0.01) along with an iso-osmotic liquid absorption, (b) with disulfonic-stilbene (0.1 mM), amiloride (0.7 mM), acetazolamide (0.1 mM), or ouabain (0.5 mM) Na+ did not change and Cl- decreased less (P less than 0.01) than with Ringer. With gluconate-Ringer or methylglucamine-Ringer the liquid flow reversed: in the former case Cl- and, to a smaller extent, Na+ increased (P less than 0.01); in the latter only Na+ increased (P less than 0.01). These findings suggest: (1) the occurrence of a Na+/H+ and Cl-/HCO3- double exchange on the serosal side and of a Na+/K+ pump on the interstitial side of the pleural mesothelium; (2) a slow efflux from the pleural space of gluconate or methylglucamine relative to the corresponding influx of Cl- or Na+, respectively; this drags liquid into the space by osmotic gradient.     

Mastering the antegrade femoral artery access in patients with symptomatic lower limb ischemia: learning curve, complications, and technical tips and tricks.

BACKGROUND: Antegrade femoral access is fraught by technical challenges and steeper learning curve, in comparison with retrograde contralateral femoral access. We appraised learning curve, complications, and technical aspects inherent in the adoption of antegrade approach. METHODS: Consecutive cases in which antegrade access was attempted by a cardiologist experienced in retrograde access, but inexperienced in antegrade, under supervision of an operator with anterograde expertise, were collected. The primary end-point was the occurrence of antegrade access failure or local complications. Major complications were defined as those life-threatening, requiring transfusion, percutaneous, or surgical repair. RESULTS: Anterograde access was attempted in 120 patients. The primary end-point occurred in 14 (11.6%) cases, but according to the learning curve, in 12 (20%) for first 60 cases vs 2 (3.3%) for the last 60 cases (P = 0.008). Access failure in the hands of the in-training operator was similarly found in all cases but one during the first 60 cases. No major complications occurred, while minor complications were found in 9 (7.5%) patients, again with all but two of them occurring in the first 60 cases. These included peri-adventitial extravasation in 8 patients (6.7%), and perforation of a small branch in one (0.8%); all these complications were conservatively and successfully managed. Obesity was the only significant predictor of access failure/complication (P = 0.004). CONCLUSIONS: This work, the first to report on the learning curve of the antegrade approach, supports the feasibility and safety of this access site even for an in-training operator, if supervised. A minimum caseload of 60 procedures is likely needed to master this technique.     

Mediterranean leishmaniasis in HIV-infected patients: Epidemiological, clinical, and diagnostic features of 22 cases

Summary Twenty-two Italian HIV-infected patients developed leishmaniasis, clinically manifested as visceral (13 cases), cutaneous (2 cases) and disseminated disease (7 cases). Twenty were males and two females (mean age: 32.8 years) with a mean CD4+ cell count of 46.8/μl at diagnosis; risk factors were intravenous drug use (17 patients) and sexual behaviour (two bisexual, two homosexual, one heterosexual). All but one patient lived or travelled in hypoendemic Italian regions and other Mediterranean countries. Apart from the two patients with cutaneous leishmaniasis, the clinico-pathological and biological spectrum of the infection was often atypical, especially in patients with disseminated disease. The diagnosis was routinely made by direct recovery of parasites in biological specimens, mainly in bone marrow aspirate, whereas serology was negative or borderline in most of the patients. Among 17in vitro isolates,Leishmania infantum was the only species involved with previously undescribed isoenzyme patterns in two cases. Treatment with antimonials and other drugs showed only temporary clinical improvement in some patients. Relapses were the rule. Leishmaniasis confirms itself as an opportunistic infection in HIV-positive persons. Secondary chemoprophylaxis should be considered in cases of relapsing disease.